1. Field of Use
This invention relates generally to a two-piece plastic support assembly releasably mountable in a hole in a panel and usable to support an object, such as a shelf or handle, associated with the panel. In particular, the invention relates to such a support assembly which is especially well-adapted for use with a foam-backed panel defining a wall or door of a storage compartment of apparatus, such as a refirgerator or freezer or the like.
2. Description of the Prior Art
The storage compartment in apparatus, such as a refrigerator or freezer or the like, is defined by walls and a door constructed of liners or panels which are backed by insulating batts or by foamed-in-place plastic thermal insulation. Such panels frequently take the form of relatively expensive steel sheets covered on one side with baked-on enamel, but low-cost pre-cast plastic panels are becoming more common. Support assemblies are mounted on the panel surfaces confronting the compartment and serve various purposes, such as supporting objects, including stationary or slidably movable shelves, or serving as stops to limit travel of movable components, such as slidable shelves, drawers or doors. Support assemblies are also mounted on the exterior panels of which the door is constructed to support objects such as the door handle or hinges. Support assemblies take various forms but one commonly used prior art type for use in the storage compartment comprises a plastic body of some suitable shape and having bent resilient locking wires at the rear thereof which is insertable from the compartment side of the panel through a non-circular butterfly-shaped hole therein and twisted (90.degree. to 180.degree.) to cause the wires to flex and lockingly engage the rear side of the panel and lock the support assembly in position under rather tight tension. Such a prior art fastener assembly is usually employed with a metal panel, because the spring tension tends to cause a more fragile plastic panel to craze or even crack. Some other commonly used prior art one-piece type fastener assemblies require either a T-shaped panel hole or a pair of holes, such as a semi-circular hole above a smaller circular hole, to prevent rotation of the fastener assemblies when in place. In use, prior art fasteners are usually inserted in pre-formed (punched, drilled or otherwise formed) panel holes after an insulating batt is emplaced or after the plastic insulation is foamed-in-place and hardened on the rear side of the plastic panel. The manufacturing technique employing in-situ foaming requires the pre-formed panel holes to be covered by masking tape before the in-situ foaming is carried out in order to prevent liquid foam leakage therethrough and to eliminate the need to remove hardened leakage foam from the finished panel surface and thereby ensure tight sealing of the hole by the subsequently-inserted fastener assembly. Furthermore, such subsequent insertion of the fastener assembly requires that it pierce the tape and be forced into the hardened foam therebehind. This can be relatively difficult and time-consuming when done manually, if correct placement is to be acheived. Then, too, prior art support assemblies are difficult to remove and replace, if necessary, without damaging the panel or other portions of the appliance. It is also noteworthy that the externally mounted door handles which are secured to fastener assemblies suitable therefor can either be put on before unit shipment or be put on by the service man or consumer. These handles can be mounted on the face or side edges of the door panel to accomplish the final mount. There is a movement in the industry to eliminate all exterior hardware such as projecting handles, to cut down on the size of the unit shipping containers and thus allow for the increase in shipment size per tractor trailer or railroad car to further reduce costs.
The following two patents exemplify the prior art support assemblies which have wire clips associated therewith: U.S. Pat. Nos. 3,565,504 and 2,896,897. The following three patents exemplify support assemblies which are merely inserted through a hole in a panel from the compartment or front side of the panel and on which a shelf directly rests: U.S. Pat. Nos. 2,620,255, 2,665,101 and 2,657,894. The following three patents disclose multicomponent support assemblies in which a first component is inserted through a panel hole from the rear side of the panel and a second component is connected to the first component from the compartment or front side of the panel: U.S. Pat. Nos. 3,826,458, 3,264,699 and 3,917,206. In the two last-recited patents the first component is emplaced prior to in-situ installation of insulating foam. The following three patents each disclose a support assembly in which three separate components, including an expansion member such as a screw or rivet, are installed from the compartment or front side of the panel. In U.S. Pat. No. 3,469,493, a screw or pin is required in certain embodiments to effect expansion and to secure the components together in locked association in the panel hole.